The present invention relates to an original document conveyance device by which the original document is conveyed to a reading position for image reading.
A basic structure of the original document conveyance device is composed of a sheet feed tray on which original documents are stacked, a conveyance means by which the original document is conveyed from the sheet feed tray and passed the reading position, and a delivery sheet tray on which the original document passed the reading position is stacked.
In a sheet feed section to feed the original document from the sheet feed tray, there are provided, generally, a feeding means for feeding the original document in the order from the top, and a separation and conveyance means by which the fed original documents are separated to one sheet and conveyed, further, there is provided a stopping member by which ends of the original documents in front of a feed direction are made uniform and the smooth feeding is enabled, and the original document is assuredly conveyed one by one sheet.
For example, in Japanese Tokkaihei 6-227696, original document stop members 1 and 101 as a stopping member are provided in front of the feeding direction of a sheet feed roller 9 as a feeding means.
In Japanese Tokkaihei 6-227696, further, a movable stopper 2 is provided, and made so that the original document is not set going over the leading edge position. Then, it is structured in such a manner that the stopper 2 is retreated when the original document conveyance is started.
The structure in which the stopper is provided in addition to the stopping member as in Japanese Tokkaihei 6-227696, is a means by which the original document is surely conveyed one by one, and which is effective in a control of a conveyance timing or in a posture control of the conveyed original document, and the high speed reading can be conducted, however, there are problems that a mechanism becomes complicated in such a case where a drive means for driving the stopper is provided, and a cost is increased.
Further, because an operation of the stopper relates to a timing control, it is necessary to make the synchronization with the control of other parts in the original document conveyance device. Therefore, when the synchronization control is not normally conducted, the conveyance failure such as a jam is generated.